Infrared micropolarizer array fabricated using a reversal nanoimprint.

Using a reversal nanoimprint and metal evaporation process, we fabricated a micropolarizer array for the 2.5-7 μm wavelength region. The micropolarizer array has a unique unit, which is composed of 2×3 arrays on an intrinsic silicon substrate. Each array consists of a 200 nm period bilayer Al grating in a 1.3  mm×1.3  mm aperture. The transmittance of transverse magnetic polarization of each array is greater than 65% in the 2.5-7 μm wavelength range, and the extinction ratio is over 35 dB in the 3-4 μm and 6-7 μm wavelength range. This fabricated micropolarizer array has lower costs and better compatibility with microfabrication processes.